What steps should I take if I experience a tingling or pins‑and‑needles sensation in my legs while diving?

Immediate Action Required: Exit the Water and Seek Emergency Medical Evaluation

If you experience tingling or pins-and-needles sensation in your legs while diving, you must immediately abort the dive, surface safely (with controlled ascent), and seek urgent medical evaluation for possible decompression illness (DCI) or spinal cord involvement—this is a medical emergency that requires rapid assessment and potential hyperbaric oxygen therapy.

Why This Is Critical

Leg paresthesias (tingling/pins-and-needles) during or after diving represent a red flag symptom for serious diving-related injuries, particularly:

Decompression Illness (DCI)

• Decompression illness occurs when dissolved nitrogen comes out of solution as bubbles during ascent, causing tissue damage 1
• The most severe manifestations are cardiorespiratory and neurological 1
• Symptoms include limb pains, fatigue, malaise, and a wide range of neurological symptoms including paresthesias 1
• Spinal cord decompression sickness is particularly concerning and presents with paresthesias, leg weakness, lower back pain, or abdominal pain 2

Time-Sensitive Nature

• The presence of initial motor impairment and emergence of sphincter dysfunction are predictive of poor prognosis regardless of treatment 3
• Spinal symptoms appearing immediately on surfacing are associated with worse outcomes—only 21% of patients with immediate severe spinal symptoms achieved full recovery in one series 2
• 79% of patients with spinal cord DCI achieved full recovery when treated promptly, but delays worsen outcomes 2

Immediate Steps to Take

1. Surface Safely

• Perform a controlled ascent if still underwater
• Do NOT attempt rapid ascent as this increases risk of arterial gas embolism 1

2. Administer 100% Oxygen Immediately

• Begin breathing 100% normobaric oxygen as soon as you surface 3, 4
• Continue oxygen via demand valve if available until reaching a hyperbaric facility 4
• This is the single most important first aid measure for suspected DCI

3. Rehydrate

• Begin oral or intravenous rehydration 3
• Dehydration is a known risk factor for DCI 2

4. Contact Hyperbaric Facility Immediately

• Do not wait for diagnostic certainty—act without delay to arrange transfer to a recompression facility 5
• Pre-notify the hyperbaric chamber as they often need preparation time 4
• Secure your dive computer for the hyperbaric team to review dive profile 4

5. Avoid Further Injury

• Lie flat or in recovery position during transport
• Careful rescue and immobilization are critical 4
• Do NOT fly or ascend to altitude before recompression therapy

Critical Context: This Can Happen on "Safe" Dives

A crucial pitfall: 41% of spinal cord DCI cases occurred on dives within the decompression limits of standard dive tables 2. This means:

• You can develop DCI even on apparently shallow or "safe" dives 5
• Risk factors include fatigue, dehydration, and extreme physical effort 2
• Standard dive tables may not be completely safe for all sport divers 2

Why Leg Symptoms Are Particularly Concerning

The spinal cord is especially vulnerable during diving because:

• Bubble formation in spinal tissues can cause direct neurological damage 1
• The outcome is unpredictable during the first 24 hours with high risk of incomplete recovery 3
• Even mild spinal symptoms identified on surfacing should be treated vigorously 2

Differential Considerations

While DCI is the primary concern, the evaluation should also consider:

• Arterial gas embolism from pulmonary barotrauma (can present with neurological symptoms) 1
• Other medical conditions that may mimic diving accidents 6
• However, treat as DCI first until proven otherwise—delays in treatment worsen outcomes

Treatment Expectations

• Recompression therapy in a hyperbaric chamber is the definitive treatment 3, 2
• Most patients receive US Navy treatment tables using oxygen 2
• Severe cases may benefit from oxygen-helium therapy 2
• There is no specific medical therapy for DCI other than hyperbaric treatment 4

Bottom line: Leg tingling while diving is a neurological emergency until proven otherwise. Surface safely, breathe 100% oxygen, and get to a hyperbaric chamber immediately—do not delay for diagnostic certainty.